Resting energy expenditure in cancer patients before and after gastrointestinal surgery.

The aim of this study was to assess the impact of surgical trauma on energy metabolism in cancer patients. Therefore, resting energy expenditure (REE) was determined before and after surgery in patients with newly detection gastric and colorectal cancer. Preoperative REE was measured in 104 patients. In 65 of these 104 patients REE was also measured on the seventh or eighth postoperative day. Postoperative REE was significantly higher than preoperative REE (mean +/- SD: 1471 +/- 238 vs 1376 +/- 231 kcal; p less than 0.001). After surgery 22 patients were hypermetabolic (REE greater than or equal to 115% predicted energy expenditure) compared with seven hypermetabolic patients before surgery. This hypermetabolism in the postoperative state can be explained by the administration of total parenteral nutrition (TPN), by an increased body temperature mainly as a consequence of postoperative complications and by the surgical trauma itself. Patients who received preoperative TPN (n = 12) showed a 10% increase in REE. Thirteen patients suffered from minor and major postoperative complications; postoperative REE in this group was increased by 10%. Forty patients who had undergone uncomplicated surgery showed a slight but significant increase of 3% in REE after operation. We conclude from this study that the increase in REE resulting from surgical trauma itself is modest at the seventh to eighth postoperative day. Therefore, energy requirements for patients undergoing major elective surgical stress are lower than generally presumed.